Device for shaping rectangular magnetic core from circular magnetic core

ABSTRACT

The present invention relates to fabrication of magnetic cores of electromagnetic apparatuses and more specifically it relates to devices for shaping rectangular magnetic cores from circular magnetic cores usually wound from electrical steel strip.

United States Patent Mescheryakov 1 1 Apr. 8, 1975 1 1 DEVICE FOR SHAPING RECTANGULAR 2.4611139 2/1949 Ncutlings 113/120 M MAGNETIC CORE FROM CIRCULAR 3.034.734 4/1963 Richardson .lr 29/203 D 3.220.239 11/1965 Olsen ct all 1 72/394 MAGNETIC CORE 3.322.910 12/1965 Roper 9 1 72/418 [76] Inventor: Mikhail Grigorievich Mescheryakov, 3.443.413 5/1969 Roper 1 1 3/3 9 ulitsa Karla Marx- 53 [4 3.535.907 ill/I970 Winter 1 1 1 72/401 ly Kuibvshcvskoi ohlusti 3.621.699 l l/l97l Valck et a1. 72/4114 USISR 1759.203 9/1973 Frankenberg 113/120 M [22] Filed: Aug. 13 1973 FOREIGN PATENTS OR APPLICATIONS 778545 7/1957 United Kingdom 113/120 M [21] Appl. No; 387,813

Primary livuminer-C. W. Lanham 521 11.5. c1 72/401; 29/203 D 14mm"! Keenan [51] Int. Cl. B2ld 3/14 158 Field 01 Search 72/394. 399.401.4112, 1 1 ABSTRACT 72/404, 418; 113/120 M; 29/203 D 205 D, The present invention relates to fabrication of mag- 29/211 D netic cores of electromagnetic apparatuses and more specifically it relates to devices for shaping rectangu- [56] References Cited lar magnetic cores from circular magnetic cores usu- UNITED STATES PATENTS ally wound from electrical steel strip.

756,832 4/1904 Cleveland 113/120 M 9 Claims. 6 Drawing Figures DEVICE FOR SHAPING RECTANGULAR MAGNETIC CORE FROM CIRCULAR MAGNETIC CORE The essence of the invention lies in that the device for shaping a rectangular magnetic core from a circular magnetic core comprises shaping jaws of which at least one is movable, said jaws being located on a base and facing each other, a shaping zone between said shaping jaws, a guide of said movable shaping jaw ensuring its progressive movement towards the opposite jaw, a mandrel located in the shaping zone and passing through the opening in the circular magnetic core located in the shaping zone. a drive for actuating said movable shaping jaw and for building up the force required in shaping the rectangular magnetic core from a circular magnetic core which additionally comprises at least two fixed stops located on said base between said shaping jaws while said mandrel is split into at least two parts installed, each, with a provision for reciprocating between the opposite part and the corresponding fixed stop, said parts of the mandrel being kinematically linked with said shaping jaws so that the closing of said shaping jaws spreads apart said parts of said mandrel.

The present invention relates to the electrical engineering; more specifically it relates to the manufacture of magnetic cores for electromagnetic apparatuses and still more specifically, to the devices for shaping rectangular magnetic cores from circular magnetic cores.

Known in the art is a method according to which the rectangular magnetic core is made of electrical steel strip wound on a rectangular mandrel whose shape and dimensions correspond to those of the opening in the magnetic core being fabricated. This method presupposes two concurrent operations. viz., winding the elec' trical steel strip on the rectangular mandrel and shaping the magnetic core to the preset size.

The basic disadvantage of this process of fabricating rectangular magnetic cores lies in its low productivity amounting to not over 60 8O magnetic cores per hour. This disadvantage is caused by the fact that the shaping of the rectangular magnetic core in the process of winding the electrical steel strip on the rectangular mandrel is effected with the aid of a pressure roller which presses down the strip constantly with a sufficiently strong force. This imposes very high dynamic loads on the rectangular mandrel and the entire device and denies the possibility of attaining high speeds and a considerable increase of productivity.

Besides, the devices for the realization ofthis method of fabricating magnetic cores with concurrent winding and shaping operations are rapidly put out of commis sion through wear and are insufficiently reliable in op eration.

Another known process of fabricating rectangular magnetic cores is characterized in that the operations of winding the core from electrical steel strip and shaping the magnetic core are separated. ln this method the first operation is winding the electrical steel strip on appropriate devices to produce a circular magnetic core after which said circular core is shaped on another device to produce a rectangular core.

Finally, there is a known device for shaping a rectangular magnetic core from a circular magnetic core (Pat. No. 204,319, Sweden).

This device comprises two pairs of shaping jaws arranged mutually perpendicular to each other; stacking plates directly contacting the surfaces of the magnetic core being shaped and placed on said shaping jaws; a solid mandrel inserted into the opening of the circular magnetic core. This mandrel limits the movement of a certain portion of the opposing surfaces of the magnetic core opening in the process of shaping but is clear of the other pair of the opposing surfaces in the magnetic core opening.

This device for shaping a rectangular magnetic core from a circular magnetic core ensures fabrication of a rectangular magnetic core with separately performed operations of winding a circular magnetic core from electrical steel strip and subsequent shaping it into a rectangular magnetic core.

This creates prerequisites for a considerable increase of productivity in the fabrication of rectangular magnetic cores.

However, said device for shaping rectangular magnetic cores from circular magnetic cores is not perfect enough, one of the reasons being the employment of a solid mandrel which, naturally, has the shape and dimensions differing from the final shape and dimensions of the opening in the rectangular magnetic core,

Firstly, the use of a solid mandrel inserted into the opening of the circular magnetic core before the beginning of shaping makes it impossible to carry out shaping and calibration throughout the entire surfaces of the opening in the rectangular magnetic core so that the shaping operation is carried out only on a limited portion of the two opposing surfaces which are in contact with the corresponding surfaces of the solid mandrel. in this case the portions ofthe magnetic core located on the perimeter of the surfaces of its opening which are out of contact with the solid mandrel cannot be formed to any shape which, in turn, results in insufficient density of the magnetic core, in high idle travel losses of the electromagnetic apparatuses incorporating such magnetic cores and in a very noisy operation of said electromagnetic apparatuses.

Secondly, the use ofa solid mandrel renders it impossible into increase considerably the productivity of said known device for shaping rectangular magnetic cores from circular magnetic cores. This is due to the fact that said solid mandrel of said known device, inserted into the opening of the circular magnetic core before the beginning of the shaping process, is an auxiliary member not belonging to the active part of the shaping device. Therefore, such a mandrel calls for repeating complex motions during each working cycle for inserting said mandrel into the opening of the circular magnetic core. Besides, said device has no functional elements intended to remove the shaped magnetic core from the shaping zone so that this has to be done subsequently by hand.

The solution of the technical problem aimed at a considerable increase in the productivity of the device for shaping rectangular magnetic cores from circular magnetic cores which is indispensable for the use of this device in the large scale, particularly automatic, flow-line production of these magnetic cores cannot be achieved by the use of the known shaping device incorporating a solid mandrel. The reason lies in that such a solution would involve a considerable complication of the design of the shaping device and an unwarranted large number of auxiliary mandrels of various intermediate sizes, installed and removed one after another during one working cycle as the shape and dimensions of the magnetic core opening gradually change in the course of shaping. This would also involve the necessity for complicated auxiliary devices for alternate installation and removal of solid mandrels in said shaping device which would reduce its efficiency considerably both regards operational reliability and productivity through introduction of complicated and repeated reciprocating-transporting. setting-up and other auxiliary mo tions.

Therefore, profound and largescale research work has been performed for finding a new solution at the level of an invention i.e., beyond the limits of ordinary designing solutions aimed at improving the already known shaping device.

An object of the invention resides in providing a sim ple and highly-productive shaping device for fabricating rectangular magnetic cores which would ensure shaping of a rectangular magnetic core from a circular magnetic core over the entire surface of its opening in' stead of over a limited part of it only. Besides, such a shaping device must be reliable in operation, ensure a complete shaping cycle beginning with inserting the mandrel into the circular magnetic core and up to remo\ing the mandrel from the shaped rectangular magnetic core and withdrawing the shaped magnetic core from the shaping zone.

The main object of the invention is to provide a simple and highly-productive shaping device for fabricat ing rectangular magnetic cores by modifying the mandrel so that it would form an active member of the shaping device and would play an active part in the shaping of a rectangular magnetic core over the entire surface of its opening.

This object is accomplished by providing a device for shaping a rectangular magnetic core from a circular magnetic core comprising shaping jaws of which at least one is movable, said jaws being located on a base, a shaping Zone between said shaping jaws, a guide of said movable shaping jaw ensuring its progressive movement towards the opposite jaw, a mandrel located in the opening of the magnetic core being shaped, a dri\e for actuating said movable shaping jaw and for building-up the force required in shaping the magnetic core in which, according to the invention, said device is provided with at least two fixed stops located on said base between said shaping jaws and in which said mandrel is split into at least two parts installed with a provision for longitudinal movement between said fixed stops and kin ematically linked with said shaping jaws so that the closing ofsaid shaping jaws would spread apart said parts of said mandrel.

it is practicable that each part of the mandrel in the device for shaping a rectangular magnetic core from a circular magnetic core according to the invention should be secured to a spindle inserted into the opening of a corresponding fixed stop which functions as a guide for said spindle, that the free end of said spindle should be provided with a check projection, and that the kinematic linkage between said part of the mandrel and the shaping jaws should be constituted by a strap which interacts with said check projection and whose ends should be articulated via shackles to said shaping jaws.

It is also practicable that this device for shaping a rectangular magnetic core from a circular magnetic core should be provided with a feeder ensuring the de livery of circular magnetic cores one by one into the shaping zone.

Said fcder in said device for shaping a rectangular magnetic core from a circular magnetic core may be made in the form of a chute arranged at such an angle to the base as to ensure the delivery of a circular magnetic core into the shaping zone under its own weight and may be provided with a cutoff device in the form of a hook which oscillates periodically in a vertical plane and, while being in the lower position, holds the circular magnetic core while after lifting it releases the circular magnetic core, allowing it to slide down into the shaping zone,

It is practicable that the device for shaping a rectangular magnetic core from a circular magnetic core according to the invention should be provided with a mechanism for transferring the shaped magnetic core onto a technological support mandrel (employed as an auxiliary element for further technological operations on shaped magnetic core), called henceforth a support mandrel", said mechanism comprising a knockout in the form of a fork located in the lower part of the shaping zone with a provision for vertical motion, kine matically linked with said drive, and a feeder delivering the calibrating mandrel to the shaping zone and setting it above the opening of the magnetic core being shaped.

Being simple in design and, accordingly, highly reliable in operation, the device for shaping a rectangular magnetic core from a circular magnetic core according to the invention gives a considerable increase in productivity (2 2.5 times) compared with the abovedescribed device with a solid mandrel located in the opening of the magnetic core being shaped and being a passive element which takes no active part in the process of shaping the magnetic core,

Splitting mandrel into two parts which are kinematically linked with the shaping device has transformed said mandrel into an active member of the shaping device which plays an active part in the process of shaping the magnetic core. This ensures the final forming ofthe rectangular magnetic core to a preset shape and predetermined dimensions, a tight contact between its layers and, as a consequence, a high density of the entire shaped magnetic core,

Besides, the device for shaping rectangular magnetic cores from circular magnetic cores according to the invention can be easily built into a processing line for the fabrication of rectangular wound magnetic cores due to the provision in said device of a feeder which delivers the circular magnetic cores one by one into the shaping zone and of a mechanism which transfers the shaped magnetic core onto the support mandrel.

Now the invention will be described in detail by way of example with reference to the accompanying drawings in which:

FIGv l is an elementary diagram of the device for shaping a rectangular magnetic core from a circular magnetic core according to the invention, general view;

PK]. 2 same, a section taken along line ll II in FIG. 1;

FIG. 3 same, a functional diagram;

FIG, 4 shows a circular magnetic core;

FIG. 5 shows a rectangular magnetic core,

FIG, 6 shows a knockout.

The device for shaping a rectangular magnetic core from a circular magnetic core according to the invention comprises a feeder 2 which delivers circular magnetic cores 3 one by one into a shaping zone 4., a split mandrel 5 located in the shaping zone 4. a mechanism for transferring a shaped rectangular magnetic core 6 onto a calibrating mandrel 7, movable shaping jaws 8 and 9 installed on spindles 10, fixed stops 1] and 12 installed between movable shapingjaws 8 and 9, all these elements being mounted on a common base 1 (FIGS. 1 and 2).

The split mandrel 5 consists of two parts 13 and 14 which are capable of moving longitudinally between the fixed stops 11 and 12.

Besides. there is a drive 15 intended to actuate the shaping jaws 8 and 9 and to build-up the force required for shaping the rectangular magnetic core 6. One part 13 of the mandrel 5 is secured on a spindle 16 whose free end is provided with a check projection 17. This spindle 16 passes through an opening (not shown in the drawing) in the fixed stop 12, said opening serving as a guide for said spindle 16. The second part 14 of the mandrel 5 is secured on a spindle 18 (FIG. 3) whose free end is provided with a check projection 19. This spindle l8 passes through an opening 20 in the fixed stop 11, said opening serving as a guide for said spindle 18. The kinematic linkage of the part 13 of the mandrel 5 with the shaping jaws 8 and 9 is ensured by a strap 21 interacting with the check projection 17, and shackles 22 and 23 articulated with the strap 2] and the shaping jaws 8 and 9, respectively.

The kinematic linkage between the second part 14 of the mandrel S and the shaping jaws 8 and 9 is ensured by a strap 24 (FIGS. 1 3) interacting with a check projection 19, and by shackles 25, 26 articulated with the strap 24 and the shaping jaws 8 and 9, respectively. Each shackle is articulated to the strap and the shaping jaw with the aid of a pivot 27.

The working part of the shaping jaw 8 facing the shaping zone 4 is a flat surface arranged perpendicularly to the base 1. The working part ofthe shaping jaw 9 facing the shaping zone 4 is also a flat surface arranged perpendicularly to the base 1. The working surfaces of both shaping jaws 8 and 9 are parallel to each other. Each of the shaping jaws 8 and 9 is linked kinematically with the drive 15.

The shapingjaws 8 and 9 have common guides in the form of spindles 10 on which they are movably installed; said guides allow each shaping jaw to move only perpendicularly to its working surface, either towards or away from the centre of the shaping zone.

The fixed stops 11 and 12 are installed on the base 1 between the shaping jaws 8 and 9. The fixed stop 11 is located at one end of the shaping jaws 8 and 9 and the fixed stop 12, at the other. Each of the fixed stops ll, l2 has a working part facing the shaping zone, made in the form of a flat surface and arranged square to the base 1 and to the working surfaces of the shaping jaws 8 and 9.

The working parts of the fixed stops 1] and 12 are located at a distance from each other which is equal to one of the external transverse dimensions of the fabricated rectangular magnetic core. The width of the working part of each fixed stop 11, 12, i.e., the dimension of this working part in the direction between the shaping jaws 8 and 9 is equal to the other external transverse dimension of the fabricated rectangular magnetic core 6. Obviously, the distance between the working parts of the shaping jaws 8 and 9 at the end of shaping the rectangular magnetic core 6 is also equal to the other external transverse dimension of the fabricated rectangular magnetic core 6 and, consequently. is equal to the width of the working part of the fixed stop ll, 12.

The distance between the working parts of the shaping jaws 8 and 9 at the beginning of the process of shap ing the rectangular magnetic core 6 from the circular magnetic core 3 is made a little larger than the outside diameter of the circular magnetic core so as to accommodate the latter easily in the shaping zone 4.

It should be borne in mind that the height of the circular magnetic core 3 and that of the rectangular magnetic core 6 shaped from it does not change in the course of shaping. Only the transverse dimensions of the magnetic core change in the course of shaping. It must be understood that the transverse dimensions of the circular magnetic core are its outside and inside diameters. The inside diameter of the circular magnetic core 3 is also referred to as the diameter of the opening in the magnetic core 3. It is also clear that the rectangular magnetic core has two external transverse dimensions: the width (or length) of the rectangular magnetic core 6 and. correspondingly, the length (or width) of the rectangular magnetic core 6. Similarly. there are two inside dimensions. viz. the width (or length) of the opening in the rectangular magnetic core 6 and. cone spondingly, the length (or width) of the opening in the rectangular magnetic core 6.

In the actual embodiment of the device for shaping the rectangular magnetic core 6 from the circular mag netic core 3 considered here one of the external transverse dimensions determining the distance between the working parts of the fixed stops ll and 12 is the length of the fabricated rectangular magnetic core 6 while the other external transverse dimension determining the width of the working part of each fixed stop 1]. 12 is the width of the fabricated rectangular magnetic core 6.

Each part 13 and 14 of the split mandrel 5 is made in the form of a parallelepiped whose height is equal to the height of the shaped circular magnetic core 3 and, consequently, to the height of the fabricated rectangular magnetic core 6. The width of this parallelepiped is equal to the inside dimension of the fabricated rectangular magnetic core 6 corresponding to its other outside dimension. It is obvious that in the considered embodiment of the device for shaping the rectangular magnetic core 6 from the circular magnetic core 3 such an internal dimension of the fabricated rectangular magnetic core 6 determining the width of said parallelepiped whose shape is repeated by each part 13 and 14 of the split mandrel 5 is the width of the opening in this magnetic core. The sides of the parts 13 and 14 of the split mandrel 5 facing the fixed stop 12 and ll, respectively, are the working surfaces of said parts 13 and 14 of the split mandrel 5 which transmit the required force to the magnetic core being shaped from the side of its opening while the working parts of the shaping jaws 8 and 9 apply the required force to the external parts of the magnetic core facing the said jaws. The distance between the working surfaces of the parts 13 and 14 of the split mandrel 5 at the beginning of the process of forming the rectangular magnetic core 6 from the circular magnetic core 3 is selected so as to ensure free entrance of the split mandrel 5 into the opening of the circular magnetic core when the latter is located in the shaping zone 4. The kinematic linkage of the parts 13 and 14 of the split mandrel with the shaping jaws 8 and 9 is made so that at the end of the process of shaping the distance between the working surfaces of the parts 13 and 14 of the split mandrel 5 is equal to the length of the opening in the fabricated rectangular magnetic core 6.

The feeder 2 which delivers the circular magnetic cores 3 one by one into the shaping zone 4 comprises a chute 28 and a cutoff hook 29. The chute 28 is set at 30 40 to the surface of the base 1. At such an inclination angle of the chute 28 the gravity force component of the circular magnetic core 3 located on the chute 28 and acting down along said chute exceeds considerably the force of friction. Therefore. ifthe circular magnetic core 3 on the chute 28 is not arrested. it will slide down the chute and, since the lower end 30 of the chute is located close to the shaping zone 4, said circular magnetic core 3 will enter the shaping zone 4 and occupy the initial position before shaping. The cut off hook 29 is fastened by one end 31 on a pivot 32. while its other free end 33 is bent at an approximately right angle and. being in the lower position. holds the next circular magnetic core 3 which is ready to be fed into the shaping zone 4. It is clear that this will also hold all the other circular magnetic cores 3 located on the chute 28.

The mechanism for transferring the shaped rectangular magnetic core 6 onto the support mandrel 7 comprises a knockout 34 in the form of a fork located in the lower part of the shaping zone with a provision for vertical movement and a feeder 35 of the support man drel which delivers the support mandrel 7 to the shaping zone and positions it above the opening ofthe magnetic core being shaped.

In the subsequent description ofthe device according to the invention and of the interaction of its units and parts use shall be made of some dimensional relations pertaining to the dimensions of the magnetic core being shaped. Therefore, let us consider the main dimensional relations of the circular 3 and rectangular 4 magnetic cores.

The space 36 (FIG. 4) of the circular magnetic core limited by the surfaces of its faces 37 and the internal cylindrical surface 38 is known as the magnetic core opening. The basic dimensions ofthe circular magnetic core are inside diameter at (opening diameter), outside diameter D, thickness C and height h.

In the case of the rectangular magnetic core the opening 39 (FIG. 5) is also the space limited by the surfaces of its faces 40 and the internal surface 41.

The main dimensions of the rectangular magnetic core are the length a and width b of its opening, thickness C height h and the external dimensions, viz., E (length) and F (width).

The knock-out 34 of the mechanism for transferring the shaped rectangular magnetic core 6 (FIG. 1) made in the form of a fork has two upward directed projections 42 and 43 (FIG. 6) secured on a common base 44. Said base 44 of the projections 42 and 43 is mounted on a rod 45 whose end is provided with a roller 46 mounted on a pivot 47. The distance m between the internal opposing walls of the projections 42 and 43 is ap proximately equal to, but not smaller than, the width b of the opening 39 in the shaped rectangular magnetic core. The distance n between the external walls of the projections 42 and 43 is approximately equal to. but

not larger than. the external dimension F (width) ofthe shaped magnetic core.

The length L of the projections 42 and 43 is approximately equal to. but not larger than, the external dimension E (length) of the shaped rectangular magnetic core and, finally, the height H of the projections 42 and 43 should be somewhat larger than the height h of the shaped rectangular magnetic core so as to ensure knocking the shaped rectangular magnetic core 6 out of the shaping zone 4 with the knock-out 34 (FIGS. 2 3) in the upper position.

The feeder 35 of the support mandrel comprises a magazine 48 of support mandrels. a pusher 49 which discharges the next support mandrel 7 from the magazine 48; a rammer 50 directly interacting with the support mandrel discharged from the magazine 48 when said mandrel is fed to the shaping zone 4 and set above the opening ofthe magnetic core being shaped; a guide 51 of the rammer 50. The drive 15 actuating the movable shapingjaws and building up the force required for shaping the magnetic core in the given embodiment of the device according to the invention ensures also the functioning of the mechanism for transferring the shaped rectangular magnetic core 6 onto the support mandrel 7, the operation ofthe cut off book 29 and the required interaction as well as the preset sequence of interaction of all the elements and of the entire device for shaping rectangular magnetic cores from circular magnetic cores according to the invention.

The drive is comprised of the following basic units: an electric motor 52; a speed reducer 53, a kinematic chain 54 for transmitting motion to the shaping jaws 8 and 9; a camshaft 55; a kinematic chain 56 for imparting motion to the knock-out 34; a kinematic chain 57 for conveying motion to the cut-off hook 29 and pusher 49; and a kinematic chain 58 for transmitting motion to the rammer 50.

The speed reducer 53 consists of a worm pair comprised of a worm 59 and a worm gear 60. The worm 59 is mounted on a shaft 61 rotating in bearings 62 and is connected with the shaft 64 of the electric motor 62 by a coupling 63. The worm gear is mounted on a shaft 65 which rotates in bearings 66 and carries a driving sprocket 67 of the chain drive 68 and the driving gear 69 of the kinematic chain 54. The kinematic chain 54 consists of a driving gear 69 meshing with driven gears 70 and 71; a shaft mounted in bearings 73 and carrying a gear 70; a crank 74; a connecting rod 75 installed in a bearing 76 and connected rigidly with the shaping jaw 9; a shaft 77 rotating in bearings 78 and carrying the gear 71; a crank 79 and a connecting rod 80 installed in a bearing (not shown in the drawings) rigidly connected with the shaping jaw 8.

The chain drive 68 consists of the driving sprocket 67, a driven sprocket 81 mounted on the chamshaft 55, and a chain which transmits motion from the driving sprocket 67 to the driven sprocket 81 and, consequently, to the camshaft 55.

The camshaft 55 is installed in bearings 83 and carries rigidly secured cams 84 and 85 and a driving spiraltooth gear 86 of the kinematic chain 58.

The kinematic chain 56 transmitting motion to the knockout 34 consists of a cam 84; a roller 46 interacting with said cam and mounted on a pivot 47 in the lower part of a rod 45 which is capable of moving longitudinally in a guide 87, and a spring 88 which loads the knock-out 34.

The kinematic chain 57 transmitting motion to the cut-off hook 29 and pusher 49 comprises: a cam 85; a roller 89 interacting with said cam; a lever 90 one end of which is rigidly secured on a pivot 91 while its other end carries said roller 89; a spring 92 which presses the roller 89 against the cam 85; a toothed quadrant 93 mounted on a pivot 91; a gear rack 94 interacting with said toothed quadrant 93 and connected rigidly with the pusher 49; a guide 95 of the gear rack 94; a lever 96 rigidly secured on the pivot 91; a lever 97 secured rigidly on the pivot 32 of the cut-off hook 31; a rod 98 interconnecting the free ends of said levers 96 and 97 by means of pivots 99. The pivot 91 is installed in bearings 100.

The kinematic chain 58 transmitting motion to the rammer comprises the driving spiral tooth gear 86; a driven spiral tooth gear 101 meshing with the driving spiral tooth gear 86 and mounted on a pivot 102 installed in bearings 103; a cam 104 mounted on the pivot 102 which is installed in bearings 103; a cam 104 mounted on the pivot 102; a roller 105 interacting with the cam 104 and installed movably on a lever 107 with the aid of a pivot 106; a pivot 108 installed in bearings 109 and carrying rigidly-mounted levers 107 and 110 and a toothed quadrant 111; a spring 112 which presses the roller 105 against the cam 104; a gear rack 113 meshing with the toothed quadrant 111; a guide 114 of the gear rack 113. The end of the gear rack 113 facing the shaping zone 4 is rigidly connected with the rammer 50.

While studying the above-listed units and parts of the device for shaping rectangular magnetic cores from circular magnetic cores according to the invention in the drawings (FIGS. 1 through 6) it should be noted that these drawings. particularly FIGS. 1 and 2, are made with a view to illustrate in the clearest possible way the maximum number of parts and units and to show their mechanical or kinematic connections.

For this purpose FIG. 1 gives a partial cutout of the driven gear 71 of the kinematic chain 54 for transmitting motion to the shaping jaws 8 and 9 and of the shaft 77 of this gear with the removed guide 51 of the rammer 50 and the removed strap 24 and shackles 25, 26. Besides, the cutout in the base 1 in FIG. 1 is intended to show a part of the camshaft 55, the driven sprocket 81 and the chain 82 of the chain drive 68.

FIG. 2 which is a section of FIG. 1 along the longitudinal vertical plane 11 II shows this section only in a part of the shaping zone in order to visualize better the arrangement of the knock-out 34 for the shaped magnetic core, the position of the support mandrel 7 in the rammer when said mandrel is being fed into the shaping zone 4, the rammer guide 51 and the shaping zone 4.

The mechanism for transferring the shaped rectangular magnetic core 6 onto the support mandrel 7 consists of two units located at a certain distance from each other. i.e., the knock-out 34 and the feeder 35 interconnected kinematically and functionally. That is why this mechanism is not denoted by a special reference number in the drawings.

It is obvious that the drive for actuating the shaping jaws and building-up the force required for shaping the magnetic core can be used only for its direct purpose in the other embodiments of the invention whereas the knock-out 34, the feeder of the support mandrel 35 and even the cutoff hook can be fitted, each, with a drive of its own. In this case a corresponding programming device should be installed for ensuring the required interaction of all the units and parts of the device for shaping a rectangular magnetic core from a circular magnetic core.

In the embodiment of the invention considered above it is understood from the above that the function of such a programming device is fulfilled by the camshaft 55 with the corresponding cams 84, 85 and 104.

Now. let us consider the operating process of the device from the moment of completing the shaping of the rectangular magnetic core 6 (FIG. 1) when said magnetic core has been transferred onto the corresponding support mandrel and withdrawn from the shaping zone 4 but has not yet been discharged from the device considered here.

The positions of all the units and parts of the considered embodiment of the device according to the invention at this moment of time are shown in the functional diagram (FIG. 3). Assuming that this intermediate po sition is the initial one, the individual units and parts of the device will occupy the following positions.

The shaping jaws 8 and 9 are closed. The cut-off hook 29 is lowered and its end 33 holds the circular magnetic core 3 on the chute 28 of the feeder 2. The knock-out 34 occupies an intermediate position in which the face surfaces of the upper ends of the projections 42 and 43 are somewhat below the plane of the upper faces of the shapingjaws 8, 9 and fixed stops 1], l2.

The rammer 50 is in an intermediate position between the shaping zone 4 and the extreme left position in which it will be located opposite the lowermost support mandrel 7 out of the number of such calibrating mandrels held by the magazine 48. Inasmuch as the considered device is in operation at the given moment of time, the electric motor 52 is switched on and its shaft 64 rotates in a clockwise direction (as shown in FIG. 3). This rotation of the shaft 64 of the electric motor 52 is transmitted by the coupling 63 to the shaft 61 of the worm 59 which is the input shaft of the speed reducer 53, and to the worm 59 carried by this shaft 61. The worm 59 meshes with the worm gear 60 which rotates clockwise (as shown in the drawing) and transmits rotary motion to the shaft 65 on which it is rigidly mounted and which functions as the output shaft of the speed reducer 53. Inasmuch as the driving sprocket 67 of the chain drive 68 and the driving gear 69 of the kinematic chain 54 are rigidly secured on said shaft 65 they rotate clockwise too. The speed reducer 53 is intended to decrease the speed of rotation. Hence, the shaft 65 of the worm gear 60 which is the output shaft of the speed reducer 53 as well as the driving sprocket 67 and driving gear 69 also rigidly mounted on this shaft will rotate at a lower speed than the rotation speed of the shaft 61, said lower speed being determined by the speed ratio of the worm pair.

The driving sprocket 67 of the chain drive 68 transmits motion via the chain 82 to the driven sprocket 81 rigidly secured on the camshaft 55 and, consequently, to the camshaft 55 which rotates in a clockwise direction (as shown in the drawing). The driving gear 69 meshing with the driven gears and 71 rotates the Iatter in a counterclockwise direction.

The shaft 72 of the driven gear 70 rotates together with the latter actuating the crank assembly consisting of the crank 74 and the connecting rod and converting the rotary motion of the shaft 72 into the reciproiting motion transmitted to the shaping jaw 9. The aft 77 of the driven gear 7l rotates together with the tter, setting in motion the crank assembly which conits of the crank 79 and the connecting rod 8 and con :rts the rotary motion of the shaft 77 into the recipro iting motion transmitted to the shaping jaw 8.

As the camshaft 55 rotates clockwise, the earns 84, i and the spiral-tooth gear 86 rigidly mounted on this .aft rotate clockwise too. The cam 84 interacting with e roller 46 of the knockout 34 rolling over its cylin 'ical surface lifts periodically the roller 46 and. conseiently. the knock-out 34 to the uppermost position hen the portion US of the cam 84 comes under the ller 46 and the face surfaces of the upper ends of the -ojections 42 and 43 are in the same plane with the )per edges of the shaping jaws 8,9 and fixed stops 1 1., Z. The knock-out 34 is lowered to the downmost posi- Jn by the spring 88 when the portion 116 of the cam l comes under the roller 46. Shown in FIG. 3 is an in rmediate position of the cam 84 in which the portion l of the cam 84 farthest from the axis ofthe shaft 55 is moved away from the roiler 46 while the portion [6 of the cam 84 nearest to the axis of the shaft 55 has )1 yet approached the roller 46.

The cam 85 interacting with the roller 89 which rolls zer its cylindrical surface lifts periodically the roller J and. consequently the lever 90 on which said roller movably secured, to the uppermost position in which e portion 117 of the cam 85 comes under the roller 9. The lever 90 rigidly connected with the pivot 91 rns the latter to one of the extreme positions in which 1e toothed quadrant 93 mounted on the pivot 9| will :t on the gear rack 94 so that the pusher 49 will come it of the lower part of the magazine 48; all the support andrels 7 accommodated in the magazine 48 will go Jwn a distance equal to the height of one support andrel 7 and the lowermost mandrel will occupy the ace previously occupied by the pusher 49.

Besides, the cutoff hook 29 will rise and its free end 3 will release the circular magnetic core 3 which will 2 able to slide down the chute 28 into the shaping The lever 90 is lowered to the downmost position by m spring 92 when the portion 118 of the cam 85 )mes under the roller 89. Shown in FIG. 3 is an interediate position of the cam 85 when the portion 117 fthe cam 85 that is farthest from the axis of the shaft 5 has moved away from the roller 89 whereas the poron 118 of the cam 85 that is nearest to the axis of the raft 55 has not yet approached the roller 89. It should 2 noted that when the lever 90 is in the downmost potion the pusher 49 that has pushed out the last support lflfldl'El 7 from the magazine 48 takes the place of this iwer support mandrel 7 and holds all the other manrels 7 accommodated in the magazine in the previusly occupied places. The cut-off hook 29 will lift and :lease the circular magnetic core 3 only after the poron 117 of the cam 85 will have come under the roller 9. In all the other positions of the cam 85 the cut-off ook 29 holds both the first incoming circular magnetic are 3 and all the other circular magnetic cores preenting them from sliding down over the chute 28.

The driving spiral-tooth gear 86 meshing with the riven spiral-tooth gear 101 rotates the latter in a lockwise direction (as shown in the drawing) and. as consequence. rotates its pivot and the cam 104 rigidly wanted on said pivot 102.

The cam 104 interacting with the roller 105 which rolls over its cylindrical surface lifts periodically the roller I05 and. consequently, the lever 107 on which said roller is movahly secured; the lever 107 is lifted to the uppermost position in which the portion 119 of the cam 104 comes under the roller 105; the lever 107 rigidly connected with the pivot l08 turns the latter to one of the extreme positions in which the toothed quadrant Ill mounted on the pivot acts on the gear rack 113 so that the rammer 50 will take a position above the shap ing zone 4 and set the support mandrel accurately above the opening of the shaped rectangular magnetic core. The lever 107 is lowered to the downmost position by the spring 112 when the portion 120 of the cam 104 comes under the roller I05. Shown in FIG. 3 is an intermediate position of the cam 24 in which the por tion ll) of the cam [04 that is farthest from the pivot 102 has already moved away from the roller 105 while the portion 120 of the cam 104 that is nearest to the pivot 102 has not yet approached the roller 105.

Now let us consider the entire working cycle of shaping the rectangular magnetic core 6 from the circular magnetic core 3 beginning from the moment which the rammer 50 occupies the extreme position (on the left in the drawing) opposite the lowermost support mandrel 7 of the magazine 48 when the roller 105 is rolling over the portion 120 of the cam 104. At the same time the portion 118 of the cam comes under the roller 89, the lever goes to the downmost position and turns the pivot 91 to the other extreme position in which the pusher 49 enters the bottom of the magazine 48 and pushes out the lowermost support mandrel; the latter enters the rammer 50 and pushes from it and, consequently, from the device according to the invention the shaped rectangular magnetic core which is transferred on to the preceding support mandrel.

Somewhat before the moment of time considered here, when the roller 89 has been dwelling on the portion 117 of the cam 85, the cut-off hook 29 has risen to the uppermost position, released the next incoming circular magnetic core 3 and the latter has entered the shaping zone 4. At this moment the shaping jaws 8 and 9 have been spread apart to a maximum distance which is larger than the outside diameter of the circular magnetic core while the parts 13 and 14 of the mandrel have been brought together so that the maximum external dimension of the mandrel (along the diagonal from one corner of the mandrel part 13 to the opposite corner of the mandrel part 14) has been smaller than the inside diameter of the circular magnetic core. Therefore, the circular magnetic core to be shaped has been accommodated between the shaping jaws 8, 9 and the fixed stops ll, 12 on the projections 42, 43 of the knock-out 34, while the movable parts of the mandrel have entered the opening of the circular magnetic core.

By the moment of time considered here the knockout has been lowered to the downmost position in which the portion 116 of the cam 84 is under the roller 46 and the circular magnetic core has taken the initial position in the shaping zone 4, ready for being shaped.

Now the magnetic core 6 iocated in the shaping zone is being shaped concurrently with delivering the support mandrel into the shaping zone 4 and positioning it above the opening of the rectangular magnetic core being shaped.

The process of shaping consists in the action of the shaping jaws 8, 9 and the mandrel parts l3, 14 on the shaped magnetic core. This is effected as follows. Rotating, the driving gear 69 of the kinematic chain 54 rotates the driven gears 70 and 71. The driven gear 70 turns the crank 74 mounted on the end of the shaft 72 rigidly connected with said gear.

The crank 74 sets in motion the connecting rod 75 and the shaping jaw 9 connected with said connecting rod, so that the jaw 9 moves towards the centre of the shaping zone 4.

Similarly and concurrently, the driven gear 71 turns the crank 79 mounted on the end of the shaft 77 which is rigidly connected with said gear. The crank 79 sets in motion the connecting rod 80 and the shaping jaw 8 connected with said connecting rod so that said jaw 8 moves towards the centre of the shaping zone 4. In this manner the side surfaces of both jaws 8 and 9 facing the shaping zone 4 come together and compress the circular magnetic core 3, pressing it against the corresponding faces of the mandrel parts 13 and 14.

The movement of the shaping jaws towards the centre of the shaping zone 4 is transmitted by shackles 22 and 23 to the strap 21 and by the shackles 25 and 26 to the strap 24; as a result, the straps 21 and 24 move away from the centre of the shaping zone 4 and shift the corresponding parts 13 and 14 beyond the check projections 17 and 19, moving each part 13 and 14 towards the fixed stops l2 and 11, respectively.

Thus, the mandrel parts 13 and 14 like the shaping jaws 8 and 9 take an active part in the process of shaping a rectangular magnetic core from a circular magnetic core.

Ramming of the support mandrel 7 already accommodated in the rammer 5 takes place concurrently with the above described process of shaping due to the movement of the roller 105 over the cylindrical surface of the rotating earn 104 from its portion 120 to the portion 119. When the roller 105 is in contact with the portion 119 of the cam 104, the lever I07 occupies the uppermost position and the rammer 50 (FIG. 2) is positioned directly above the shaping zone, setting the support mandrel accurately above the opening of the shaped rectangular magnetic core 6 (FIG. I).

At this moment the shaped rectangular magnetic core begins to be transferred on the support mandrel 7 located, as stated before, above its opening. This proceeds as follows.

Rotating, the cam 84 (FIGS. 1 3) comes from the position in which the roller 46 contacts the portion 116 of the cylindrical surface of the cam 84 to the position in which the roller 46 contacts the portion 115 of the cylindrical surface of the same cam. The knock-out 34 moves to the uppermost position in which the face surfaces of the upper ends of the projections 42 and 43 are located in the same plane with the upper faces of the shaping jaws 8, 9 and transfers the shaped magnetic core, namely removes it from the mandrel consisting of two parts 13 and 14, withdraws it from the shaping zone 4 and slips it on the support mandrel 7. The major force is required, naturally, for slipping the magnetic core on the support mandrel 7 because, concurrently with the above-described process of transferring, the shaping jaws 8 and 9 move apart and the parts 13 and 14 of the mandrel come together, thereby releasing the shaped rectangular magnetic core located in the shaping zone. Further, when the roller 107 rolls over the cylindrical surface of the cam 104 from its portion 119 to its portion 120, the lever 107 will be lowered by the spring I12 to the downmost position. will turn the pivot 108 with the toothed quadrant 111 to the corresponding position so that the gear rack 113 meshing with the toothed quadrant ill will come to the extreme position (left position in the drawings). The rammer 50 with the support mandrel 7 will take a position near the magazine 48 opposite the lowermost support mandrel 7 in said magazine First. the cam turns to a position in which its portion "7 comes under the roller 89 and lifts the latter and the lever to the uppermost position so that the cut-off hook releases the next incoming circular magnetic core 3, then it turns to a position in which the roller 89 will be in contact with the portion 118 of the cylindrical surface of the cam 85. The pusher 49 will enter the lower part of the magazine 48, push out the lowermost support mandrel 7 from the magazine 48 and said mandrel, in turn, will push the shaped rectan gular magnetic core, transferred on the support man drel 7, from the rammer 50 and will remain in said rammer.

Now the working cycle will be repeated over again in the sequence described above.

The device according to the invention for shaping a rectangular magnetic core from a circular magnetic core can be installed without any modifications in a production line for serial or large-scale fabrication of rectangular magnetic cores.

For this purpose it is sufficient to set the device according to the invention to a position in which the circular magnetic cores will fall from the discharge end of the core-fabricating machine onto the chute 28 of the feeder 2 and the discharged shaped magnetic cores slipped on the support mandrel will be discharged into the receiving device of the next machine in the production flow line.

I claim:

1. A device for shaping a rectangular magnetic core from a circular magnetic core comprising: a base; two shaping jaws located on said base, at least one of said jaws being movable; at least two fixed stops located on said base opposite each other between said shaping jaws; a shaping zone located between said shaping jaws and fixed stops; each of said shaping jaws having a working part directed towards a shaping zone, made in the form of a flat surface and arranged approximately perpendicularly to said, base; said working parts of the shaping jaws arranged parallel to each other; each of said fixed stops having a working part directed towards the shaping zone, made in the form of a flat surface which is arranged approximately perpendicularly to said base and said working parts of said shaping jaws; a guide of said movable shaping jaw providing for the movement of said movable shaping jaw in the direction perpendicular to its working part; said working parts of said fixed stops arranged at a distance from each other which is equal to one of the external transverse dimensions of the shaped rectangular magnetic core; a working part of each of said fixed stops whose width is equal to the other external transverse dimension of the shaped rectangular magnetic core; a mandrel carrying the magnetic core being shaped, located in the shaping zone; said mandrel split into at least two parts; said parts of the split mandrel installed with a provision for longitudinal movement between said fixed stops; each of said parts of the mandrel is made in the form of a parallelepiped whose height is approximately equal to the height of the magnetic core being shaped and whose width is approximately equal to the internal transverse dimension of the shaped rectangular magnetic core corresponding to the other external transverse dimension of said core; said parts of said mandrel linked kinematically with said shapingjaws so that on closing of said shaping jaws said parts of said mandrel are spread apart at least sufficiently for the distance between their surfaces facing the fixed stops to be equal to the internal transverse dimension of the shaped rectangular magnetic core corresponding to one of its external dimensions; a drive for actuating said shaping jaw and said parts of said mandrel and for building up the force required for shaping a rectangular magnetic core from a circular magnetic core.

2. A device for shaping a rectangular magnetic core from a circular magnetic core according to claim I wherein each of said fixed stops has an opening at the side of the shaping zone, each ofsaid parts of said man drel is secured on a spindle passing through said open ing of the corresponding fixed stop, said opening being used as a guide for said spindle whose free end has a projection while said kinematic linkage between each part of said mandrel and said shaping jaws consists of a strap interacting with said projection of said spindle, the ends of this strap being articulated by shackles with said shaping jaws.

3. A device for shaping a rectangular magnetic core from a circular magnetic core according to claim 1 comprising a feeder which delivers the circular magnetic cores one by one into the shaping zone.

4. A device for shaping a rectangular magnetic core from a circular magnetic core according to claim 2 comprising a feeder which delivers the circular mag netic cores one by one into the shaping zone.

5. A device for shaping a rectangular magnetic core from a circular magnetic core according to claim 4 wherein said feeder ensuring the piece-by-piece delivcry of circular magnetic cores into the shaping zone is made in the form of a chute located at such an angle to the base as to ensure the sliding of the circular magnetic core carried by it towards the shaping zone under the force of its own weight and is provided with a cutoff hook secured on a pivot with a provision for turning around said pivot in a vertical plane which passes along said chute thus providing for holding the circular magnetic core on the chute with the cut-off hook in the lower position and for releasing this circular magnetic core for its free movement down the chute towards the shaping Zone with the cut-off hook in the uppermost position.

6. A device for shaping a rectangular magnetic core from a circular magnetic core according to claim 1 including a mechanism for transferring the shaped rectangular magnetic core onto the support mandrel, said mechanism comprising a knock-out in the form of a fork located in the lower part of the shaping zone and capable of moving up and down, to allow the shaped rectangular magnetic core to be withdrawn for the shaping zone and pressed on the support mandrel, and a feeder delivering the support mandrel towards the shaping zone and setting said support mandrel above the opening of the shaped rectangular magnetic core.

7. A device for shaping a rectangular magnetic core from a circular magnetic core according to claim 2 including a mechanism for transferring the shaped rectangular magnetic core on the support mandrel, said mechanism comprising a knock-out in the form of a fork located in the lower part of the shaping zone and capable of moving up and down to allow the shaped rectangular magnetic core to be withdrawn from the shaping zone, and pressed on the support mandrel, and a feeder delivering the support mandrel towards the shaping zone and setting said support mandrel above the opening of the shaped rectangular magnetic core.

8. A device for shaping a rectangular magnetic core from a circular magnetic core according to claim 3 including a mechanism for transferring the shaped rectangular magnetic core on the support mandrel, said mechanism comprising a knockout in the form of a fork located in the lower part of the shaping zone anc capable of moving up and down to allow the shaped rectangular magnetic core to be withdrawn from the shaping zone and pressed on the support mandrel, and a feeder delivering the support mandrel towards the shaping zone and setting said support mandrel above the opening of the shaped rectangular magnetic core.

9. A device for shaping a rectangular magnetic core from a circular magnetic core according to claim 4 including a mechanism for transferring the shaped rectangular magnetic core on the support mandrel, said mechanism comprising a knock-out in the form of a fork located in the lower part of the shaping zone and capable of moving up and down to allow the shaped rectangular magnetic core to be withdrawn from the shaping zone and pressed on the support mandrel, and a feeder delivering the support mandrel towards the shaping zone and setting said support mandrel above the opening of the shaped rectangular magnetic core. k 

1. A device for shaping a rectangular magnetic core from a circular magnetic core comprising: a base; two shaping jaws located on said base, at least one of said jaws being movable; at least two fixed stops located on said base opposite each other between said shaping jaws; a shaping zone located between said shaping jaws and fixed stops; each of said shaping jaws having a working part directed towards a shaping zone, made in the form of a flat surface and arranged approximately perpendicularly to said base; said working parts of the shaping jaws arranged parallel to each other; each of said fixed stops having a working part directed towards the shaping zone, made in the form of a flat surface which is arranged approximately perpendicularly to said base and said working parts of said shaping jaws; a guide of said movable shaping jaw providing for the movement of said movable shaping jaw in the direction perpendicular to its working part; said working parts of said fixed stops arranged at a distance from each other which is equal to one of the external transverse dimensions of the shaped rectangular magnetic core; a working part of each of said fixed stops whose width is equal to the other external transverse dimension of the shaped rectangular magnetic core; a mandrel carrying the magnetic core being shaped, located in the shaping zone; said mandrel split into at least two parts; said parts of the split mandrel installed with a provision for longitudinal movement between said fixed stops; each of said parts of the mandrel is made in the form of a parallelepiped whose height is approximately equal to the height of the magnetic core being shaped and whose width is approximately equal to the internal transverse dimension of the shaped rectangular magnetic core corresponding to the other external transverse dimension of said core; said parts of said mandrel linked kinematically with said shaping jaws to that on closing of said shaping jaws said parts of said mandrel are spread apart at least sufficiently for the distance between their surfaces facing the fixed stops to be equal to the internal transverse dimension of the shaped rectangular magnetic core corresponding to one of its external dimensions; a drive for actuating said shaping jaw and said parts of said mandrel and for building up the force required for shaping a rectangular magnetic core from a circular magnetic core.
 2. A device for shaping a rectangular magnetic core from a circular magnetic core according to claim 1 wherein each of said fixed stops has an opening at the side of the shaping zone, each of said parts of said mandrel is secured on a spindle passing through said opening of the corresponding fixed stop, said opening being used as a guide for said spindle whose free end has a projection while said kinematic linkage between each part of said mandrel and said shaping jaws consists of a strap interacting with said projection of said spindle, the ends of this strap being articulated by shackles with said shaping jaws.
 3. A device for shaping a rectangular magnetic core from a circular magnetic core according to claim 1 comprising a feeder which delivers the circular magnetic cores one by one into the shaping zone.
 4. A device for shaping a rectangular magnetic core from a circular magnetic core according to claim 2 comprising a feeder which delivers the circular magnetic cores one by one into the shaping zone.
 5. A device for shaping a rectangular magnetic core from a circular magnetic core according to claim 4 wherein said feeder ensuring the piece-by-piece delivery of circular magnetic cores into the shaping zone is made in the form of a chute located at such an angle to the base as to ensure the sliding of the circular magnetic core carried by it towards the shaping zone under the force of its own weight and is provided with a cut-off hook secured on a pivot with a provision for turning around said pivot in a vertical plane which passes along said chute thus providing for holding the circular magnetic core on the chute with the cut-off hook in the lower position and for releasing this circular magnetic core for its free movement down the chute towards the shaping zone with the cut-off hook in the uppermost position.
 6. A device for shaping a rectangular magnetic core from a circular magnetic core according to claim 1 including a mechanism for transferring the shaped rectangular magnetic core onto the support mandrel, said mechanism comprising a knock-out in the form of a fork located in the lower part of the shaping zone and capable of moving up and down, to allow the shaped rectangular magnetic core to be withdrawn for the shaping zone and pressed on the support mandrel, and a feeder delivering the support mandrel towards the shaping zone and setting said support mandrel above the opening of the shaped rectangular magnetic core.
 7. A device for shaping a rectangular magnetic core from a circular magnetic core according to claim 2 including a mechanism for transferring the shaped rectangular magnetic core on the support mandrel, said mechanism comprising a knock-out in the form of a fork located in the lower part of the shaping zone and capable of moving up and down to allow the shaped rectangular magnetic core to be withdrawn from the shaping zone, and pressed on the support mandrel, and a feeder delivering the support mandrel towards the shaping zone and setting said support mandrel above the opening of the shaped rectangular magnetic core.
 8. A device for shaping a rectangular magnetic core from a circular magnetic core according to claim 3 including a mechanism for transferring the shaped rectangular magnetic core on the support mandrel, said mechanism comprising a knock-out in the form of a fork located in the lower part of the shaping zone anc capable of moving up and down to allow the shaped rectangular magnetic core to be withdrawn from the shaping zone and pressed on the support mandrel, and a feeder delivering the support mandrel towards the shaping zone and setting said support mandrel above the opening of the shaped rectangular magnetic core.
 9. A device for shaping a rectangular magnetic core from a circular magnetic core according to claim 4 including a mechanism for transferring the shaped rectangular magnetic core on the support mandrel, said mechanism comprising a knock-out in the form of a fork located in the lower part of the shaping zone and capable of moving up and down to allow the shaped rectangular magnetic core to be withdrawn from the shaping zone and pressed on the support mandrel, and a feeder delivering the support mandrel towards the shaping zone and setting said support mandrel above the opening of the shaped rectangular magnetic core. 